Simon Cowell is learning today… it probably isn’t a good idea to bang your friend’s wife, WHILE THEY’RE STILL MARRIED! His buddy, Andrew Silverman has filed divorce docs in New York… and he isn’t too happy about it. He’s alleging ADULTERY in seeking to end his marriage to Lauren Silverman … who is said to be pregnant with Simon’s child. If this is proven true, Simon can be forced to take a DNA test — something that’s hard to get in New York when a couple is married and the wife gets pregnant. Andrew says, “The nature of this action is: to dissolve the marriage between the parties based upon (1) the commission of acts of adultery by the defendant and (2) defendant’s cruel and inhuman treatment of the plaintiff.” Andrew also wants the judge to approve the couple’s pre-nup they signed back in 2003. We’ll have more details as they come in.